1. Field of the Invention
The present invention relates to an image coding apparatus, an image decoding apparatus, and an image decoding method for an image to be subjected to interframe coding.
2. Description of the Related Art
An image coding apparatus that uses a coding unit configured to perform interframe coding with motion compensation such as MPEG and the like on chronological ordered pictures forming an image to reduce the amount of picture data of a motion picture smaller than that in the case where interframe coding is not used, and the image decoding apparatus that decodes coded image or a picture have been widely in use recently.
When a picture including a particular region with great change with time such as the region including smoke, flare or the like, i.e., a particular region with a big amount of movement or a big amount of shift in a corresponding picture between different frames is to be coded, a conventional image coding apparatus is likely to have a big prediction error in the interframe coding.
Such a case with a big prediction error can be addressed by inserting many intra-pictures (abbreviated as I-picture) that are to be coded in respective intra-frames. A problem is still left in that the amount of coding is increased.
Japanese Patent Laid Open No. 2004-30225 discloses an apparatus for detecting smoky region.
However, with the apparatus disclosed in Japanese Patent Laid Open No. 2004-30225, no unit configured to perform coding or decoding is disclosed.